Sir Laurence Olivier said about the play Hamlet, "This is the story of a man who could not make up his mind." Hamlet continually postpones the request of his Father's Ghost to revenge his death so he can further attain knowledge about what he is doing. Hamlet's indecisiveness helps further advance the plot of the play. If he had killed his uncle the first time he had the chance, there would not have been a play.
There are many factors and reasons why Hamlet does not act swiftly and decisively. He does not have sufficient proof to his liking. Next, Hamlet pretends to act insane so he can figure out why his friends from England have shown up. Acting crazy also seems to delay the process even more. But Hamlet is disgusted at himself for delaying so attempting to gather proof is just a way to buy more time. Then, Hamlet worries that killing the King would send him to heaven.
Hamlet does not want his uncle to go to heaven even though his father never told Hamlet to make sure he does not go to heaven. Therefore, Hamlet further delays his plot for revenge. Lastly, Hamlet is so obsessed with his mother marrying so soon after her husband's death that it leads him astray from his father's goal. Hamlet not believing he has enough proof, pretending to act insane, wanting to send his father to purgatory, and his attitude towards his mother prove his inability to make the decision to kill his uncle.
Hamlet seems to have to prove to himself that his uncle actually did murder his father. Hamlet has doubts but then always has a plan to further advance his belief that his uncle killed his father. Hamlet does not believe Horatio when he tells him that...